#include <iostream> #include <algorithm> #include <set> #include <vector> using namespace std; using ll = long long; using vll = vector<ll>; #define sz(x) int(x.size()) int main() { int K, N; cin >> K >> N; ll basicCost = 0; vll points; for(int i = 1; i <= N; i++) { char Z1, Z2; ll P1, P2; cin >> Z1 >> P1 >> Z2 >> P2; if(Z1 == Z2) { basicCost += abs(P1 - P2); } else { basicCost += 1; points.push_back(P1); points.push_back(P2); } } sort(points.begin(), points.end()); ll ans = 0; for(int i = 0; i < sz(points)/2; i++) ans -= points[i]; for(int i = sz(points)/2; i < sz(points); i++) ans += points[i]; cout << ans + basicCost << '\n'; }